Monitoring Antibody Oxidation at Subunit Level Using BioPharmaView™ Software The high-quality data obtained by the X500B Q-TOF System combined with fast data processing using BioPharmaView™ software were demonstrated to be reliable tools for the automated calculation of percent modifications under stress conditions, thereby facilitating the monitoring of critical quality attributes at the subunit level during the development of biotherapeutics. Comparative Analysis of Partial and Selective Reduction of Monoclonal Antibodies using the X500B QTOF System The results acquired on the X500B benchtop QTOF mass spec system and analyzed with BioPharmaViewTM software suggest this workflow is capable of consistently and stably producing free light chain and heavy chain forms with only the interchain disulfide bonds reduced. Isotopic Resolution of Chromatographically Separated IdeS Subunits Using the X500B QTOF System Isotopically resolved IdeS subunit analysis on the X500B QTOF system provides accurate assessment of post translational modification with high mass accuracy.